A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine material properties. A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study. To determine properties of the material various laboratory tests such as proctor compaction test, Micro-Deval, Los Angeles, and grain distribution curve are conducted. To investigate how grain size distribution affects technical properties of the material, the 0/32 mm material was modified with two different samples; grain size distribution of 2/32 mm excluding superior material content, and 0+/32 mm with enhanced superior material content. The purpose of this study was to examine changes in material behavior during proctor compaction. Two aspects of changes in material behavior were emphasized in this study; the optimal water content and maximum dry density, as well as changes of both. As a reference for the limestone features, a traditional 0/32 mm tonalite material (granite) from Vällstaverket was used relating to proctor investigation. Material's resistance to abrasion and fragmentation was investigated by two methods: Micro-Deval and Los Angeles. The results were compared with other rock materials. Furthermore the bearing capacity of the material was verified by examination of the Young's modulus and degree of compaction, as well as properties of water content and dry density, at three trial areas on Gotland. This is performed with various methods such as static plate loading test, light weight deflectometer, density gauge/SDG200, and water/sand volume meter measurement test. By comparing results from different methods of measurement, it may indicate a relationship between these. Test area 3 consists of two smaller test areas which have different water content. The bearing capacity (Young's modulus) and the degree of compaction were measured after each roller passage. Different relationships were obtained between the amount of roller overpass, with Young's modulus of material; as well as degree of compaction. It was found in this study that limestone from Gotland (Hejdeby) maintain its position as construction material for the unbound layers of the road. The result from static plate load which indicated high E V2 values (Young's modulus) was obtained from the field, and it suggests that a fine bearing capacity can be achieved in the use of limestone.

Made available in DSpace on 2016-12-08T15:50:02Z (GMT). No. of bitstreams: 1 PGMS13DA012.pdf: 1980394 bytes, checksum: 6b37fb6e368ae3bf1a366a8d92ac0afa (MD5) Previous issue date: 2013-02-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of different management systems alters the chemical, physical and hydric soil, and time a conditioning variable. Long-term experiments incorporate this variable can inform the development of soil properties and their consequences on crop productivity. The objectives of this study were to evaluate the effects on the chemical, physical, and water in a Brown Oxisol and crop yield in long-term experiment under different land use systems and soil management; to evaluate the degree of compaction of Brown Oxisol limiting the growth and development of soybean. Were evaluated two experiments. The first was established in 1978 and consists of the following systems: no-tillage in winter and summer (without lime, with lime applied in surface and incorporated lime); conventional tillage in winter and summer (without lime and incorporated lime), and native forest. Chemical characteristics were evaluated in layers of 0-2.5; 2.5-5, 5-10, 10-20 e 20-40 cm, and the physical layers of 0-2.5; 2 0.5 to 5, 5-10, 10-20, 20-40, 40-60, 60-80 and 80-100 cm. The second experiment was conducted in a greenhouse where pots were mounted with 30 cm height, compressing layer of 10-20 cm to obtain the densities of soil: 0.9; 0.96; 1.02; 1.08; 1.14; 1.20 and 1.27 Mg m-3, corresponding to degrees of compaction between 75 and 105%. The use of the soil for long periods with conventional tillage increases the density in subsurface and decreases the aggregate stability (DMG) when compared with no-tillage and forest. However, the no-tillage system increases the stability of aggregates (DMG) to a level equal to the forest, in the layer 0 to 10 cm. It also increases the microporosity, the volumetric water content, water retention and water available to plants, mainly in the upper soil layers, compared to conventional tillage and forest. Generally, liming does not alter the soil physical and hydric properties. The conservation systems improve the soil chemical properties in relation to conventional system, observed by the higher content of exchangeable cations, extractable P, organic carbon and CEC, mainly in the layer 0 to 5 cm. The liming applied in surface in the no-tillage is effective in correcting soil acidity, since soil pH, in the layer 5-40 cm, is the same when lime was surface applied or incorporated. In no-tillage, the recovery in physical properties and the higher nutrient content increases crop yields. The degree of compaction that restricts the soybean crop depends on the attribute being evaluated. When the degree of compaction is over: 75% reduces root growth; 82% plant height is lower; 87% dry mass of shoots is lower; 93% reduces evapotranspiration; and 105% root growth ceases / O uso de diferentes sistemas de manejo altera os atributos químicos, físicos e hídricos do solo, sendo o tempo uma variável condicionante. Experimentos de longa duração incorporam esta variável e podem informar sobre a evolução dos atributos do solo e suas conseqüências na produtividade das culturas. Os objetivos desse trabalho foram: avaliar os efeitos nos atributos químicos, físicos e hídricos num Latossolo Bruno Alumínico típico e na produtividade das culturas agrícolas, em experimento de longa duração sob diferentes sistemas de uso e manejo do solo; avaliar o grau de compactação do Latossolo Bruno Alumínico típico limitante ao crescimento e desenvolvimento da cultura da soja. Foram avaliados dois experimentos. O primeiro foi implantado em 1978 e constitui-se nos seguintes sistemas: plantio direto no inverno e no verão (sem calcário, com calcário aplicado em superfície e com calcário incorporado); preparo convencional no inverno e verão (sem calcário e com calcário incorporado); e mata nativa. Os atributos químicos foram avaliados nas camadas de 0-2,5; 2,5-5; 5-10;10-20 e 20-40 cm e os atributos físicos nas camadas de 0-2,5; 2,5-5; 5-10; 10-20; 20-40; 40-60; 60-80 e 80-100 cm. O segundo experimento foi conduzido em casa de vegetação onde foram montados vasos com 30 cm de altura, compactando a camada de 10-20 cm para obtenção das densidades do solo: 0,9; 0,96; 1,02; 1,08; 1,14; 1,20 e 1,27 Mg m-3, o que corresponde a graus de compactação entre 75 e 105%. O uso do solo por longos períodos com preparo convencional aumenta a densidade em subsuperfície e diminui a estabilidade de agregados (DMG) quando comparado com os sistemas de plantio direto e a mata. Todavia, o sistema de plantio direto aumenta a estabilidade de agregados (DMG) para um patamar igual ao da mata, na camada de 0 a 10 cm. Também aumenta a microporosidade, a umidade volumétrica, a retenção de água e a água disponível às plantas, principalmente nas camadas superficiais do solo, em relação ao preparo convencional e a mata. De maneira geral, a calagem não altera os atributos físicos e hídricos do solo. Os sistemas conservacionistas melhoram os atributos químicos do solo, em relação ao sistema convencional, observado pelo maior teor de cátions trocáveis, P extraível, carbono orgânico e CTC, principalmente na camada de 0 a 5 cm. A calagem superficial realizada no plantio direto é eficiente na correção da acidez, uma vez que não houve diferença no pH do solo, na camada de 5 a 40 cm, quando a calagem foi superficial ou incorporada. No plantio direto, a recuperação nos atributos físicos e o maior teor de nutrientes aumenta o rendimento das culturas. O grau de compactação que restringe a cultura da soja depende do atributo que está sendo avaliado. Quando o grau de compactação é superior a: 75% reduz o crescimento de raízes; 82% a altura das plantas é menor; 87% a massa seca da parte aérea é menor; 93% reduz a evapotranspiração; e 105% cessa o crescimento radicular